Abstract 3385: Role Of Regional Geometric Dyssynchrony By Real-time Three-dimensional Echocardiography As A Determinant Of Functional Mitral Regurgitation In Patients With Acute Myocardial Infarction
Background: Functional mitral regurgitation (FMR) after myocardial infarction (MI) is associated with left ventricular (LV) dys-synchrony and increased mortality. However, determinants of FMR severity after acute MI are poorly defined. Our aim was (1) to test whether real-time Three-Dimensional echocardiography (RT-3DE) can provide insights into the mechanism of LV dys-synchrony on MR severity after MI (2) to investigate role of selective regional dys-synchrony index (DI) in prediction of FMR.
Method: RT-3DE and Doppler echo was performed on 64 consecutive patients (mean age 62.2 ± 12.5 yrs) following acute MI without cardiogenic shock and with narrow QRS complex (< 120 ms). MR Severity was assessed by vena contracta, and MR jet area/LA area. Dyssynchrony index (DI) was derived from the dispersion of time to minimum regional volume for all 16 LV segments. Pearson’s correlation and multiple linear regression analysis were used to identify the relationship between FMR and DI. Different models of LV dys-synchrony including global index and selective ring-defined (basal, middle and apical ring) regional index were all analyzed and compared.
Results: The mean LVEF was 49.6 ± 11.9% and LV end-diastolic volume (EDV) was 93.1 ± 23.8ml. All regional and global DIs were significantly correlated with FMR even after adjusting for age, LVEF and EDV (table 1⇓), with mid-wall DI being most strongly associated with MR severity.
Conclusion: RT-3DE determined mid-wall DI following MI is strongly associated with FMR. Our results suggest that selective geometric ring-defined DI has better FMR severity prediction and may provide specific approaches to the treatment of FMR complicating MI.